2-nitro-paraphenylenediamines substituted by sulphur in the 5-position, the process for their preparation, dyeing compositions in which they are present and their use in the dyeing of keratin fibres

ABSTRACT

Novel nitrobenzene compounds of the nitroparaphenylenediamine type substituted by sulphur in the 5-position are disclosed. These compounds are intended especially for the dyeing of keratin fibres and in particular human hair. A process for their preparation, dyeing compositions in which these compounds are present and a dyeing process in which these compositions are used are also disclosed.

This is a continuation of application Ser. No. 08/409,002, filed Mar.23, 1995, now abandoned.

The present invention relates to novel nitrobenzene compounds of thenitroparaphenylenediamine type substituted by sulphur in the 5-position.These compounds are intended especially for the dyeing of keratin fibresand in particular for the dyeing of human hair.

There are principally two major types of hair dyeing. The first type ofdyeing is semi-permanent dyeing or direct dyeing, which involvesdyestuffs capable of modifying the natural colouration of the hair to amore or less pronounced degree and of resisting 4 or 5 washes withshampoo. These dyestuffs are called direct dyestuffs and are usedwithout an oxidizing agent. The second type of dyeing is permanentdyeing or oxidative dyeing. This is carried out with so-called"oxidative" dyestuff precursors; these are colourless or weakly colouredcompounds which, when mixed with oxidizing products at the time of use,can produce coloured dyeing compounds by an oxidative condensationprocess.

Direct dyestuffs are very widely used in the field of hair dyeingbecause they have certain advantages over the oxidative dyestuffprecursors, in particular a reduction in the potential risks of allergyand the absence of hair sensitization due to the oxidative process.

The most widely used direct dyestuffs include the nitrobenzenederivatives, which on the one hand have a strong affinity for the hairand on the other hand, by virtue of the variety of possiblesubstituents, make it possible to cover a broad range of hues fromyellow through red to blue. However, the formulation of these dyestuffspresents problems on account of their resistance to washing, which isnot satisfactory.

SUMMARY OF THE INVENTION

The inventors have therefore sought other nitrobenzene dyestuffs whichcan have a good solubility in water, in water/alcohol mixtures and moregenerally in the customary dyeing carriers, and which can give hairdyeings with stability to washing as well as to light, the weather andperspiration.

It is in pursuit of this research that the inventors have discoverednovel 2-nitro-para-phenylenediamines substituted by sulphur in the5-position of formula (I): ##STR1## in which: n=0, 1, or 2;

R₁, R₂, R₃ and R₄, which may be identical or different, are a hydrogenatom or a linear or branched C₁ -C₄ -alkyl, C₁ -C₄ -monohydroxyalkyl, C₂-C₄ -polyhydroxyalkyl, C₁ -C₄ -aminoalkyl or C₁ -C₄ -monoalkyl or-dialkyl-amino-(C₁ -C₄)-alkyl radical; and

Z is a linear or branched C₁ -C₄ -alkyl, C₁ -C₄ -mono-hydroxyalkyl, C₂-C₄ -polyhydroxyalkyl, C₁ -C₄ -aminoalkyl, C₁ -C₄ -alkoxy-(C₁-C₄)-alkyl, C₁ -C₄ -acetylaminoalkyl, C₁ -C₄ -alkylamino-(C₁ -C₄)-alkylor C₁ -C₄ -dialkylamino-(C₁ -C₄)-alkyl radical, a C₁ -C₄-trialkylammonio-(C₁ -C₄)-alkyl radical of a C₁ -C₄ -alkyl halide or ofa C₁ -C₄ -alkyl sulphate (in other words, the C₁ -C₄ -alkyl halide or C₁-C₄ -alkyl sulphate defines the counter-ion), a substituted orunsubstituted benzyl, a substituted or unsubstituted phenyl, C₁ -C₄-sulphoalkyl or C₁ -C₄ -alkoxycarbonyl(C₁ -C₄)-alkyl radical.

The alkyl, hydroxyalkyl and alkoxyalkyl radicals are preferably themethyl, ethyl, propyl, butyl, hydroxyethyl, hydroxypropyl,dihydroxypropyl and ethoxyethyl radicals.

For reasons of steric hindrance, R₁ is preferably a hydrogen atom.

The compounds of the formula (I) can be used in the form of the freebase or in the form of a salt with acids such as hydrochloric acid,hydrobromic acid, sulphuric acid, and the like. They can therefore be inthe form of the hydrochloride, hydrobromide, sulphate, and the like.

The present invention therefore relates to novel compounds of formula(I) and their cosmetically acceptable salts.

The preferred compounds of formula (I) are selected especially from thefollowing compounds:

2-nitro-5-trimethylammonioethylthioparaphenylenediamine;

2-nitro-4-N-(β-hydroxyethyl)amino-5-(dimethyl)aminoethyl!thioparaphenylenediamine;

2-nitro-5-(β-aminoethyl)thioparaphenylenediamine;

2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-methylthioaniline;

2-nitro-5-methylthioparaphenylenediamine;

2-nitro-5-ethylthioparaphenylenediamine;

2-nitro-5-butylthioparaphenylenediamine;

2-nitro-5-β-hydroxyethylthioparaphenylenediamine;

2-nitro-5-(β,γ-dihydroxypropyl)thioparaphenylenediamine;

1,4-N-di(β-hydroxyethyl)amino-2-nitro-5-ethoxyethylthiobenzene;

2-nitro-4-N-(β-hydroxyethyl)amino-5-β-hydroxyethylthioaniline;

2-nitro-5-(paramethoxybenzyl)thioparaphenylenediamine;

2-nitro-4-N-(β-aminoethyl)amino-5-methylthioaniline;

2-nitro-4-N-(diethylaminoethyl)amino-5-methylthioaniline;

2-nitro-4-N-(diethylaminoethyl)amino-5-ethylthioaniline;

2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-acetylaminoethylthioaniline;

2-nitro-5-acetylaminoethylthioparaphenylenediamine;

2-nitro-5- (dimethyl)aminoethyl!thioparaphenylenediamine;

2-nitro-5-(β-aminoethyl)thioparaphenylenediamine;

2-nitro-4-amino-5-(β-hydroxypropyl)thio-N-(methyl)aniline;

2-nitro-4-amino-5-(parahydroxyphenyl)thio-N-(methyl)aniline;

2-nitro-5-ethoxycarbonylethylthioparaphenylenediamine;

2-nitro-5-methylsulphinylparaphenylenediamine;

2-nitro-5-mesylparaphenylenediamine;

1-N-(β-hydroxyethyl)amino-2-nitro-4-N,N-bis(β-hydroxyethyl)amino-5-isopropylthiobenzene;

2-nitro-5-sulphoethylthioparaphenylenediamine; and salts thereof.

The following may be mentioned among the more particularly preferredcompounds of formula (I):

2-nitro-5-trimethylammonioethylthioparaphenylenediamine;

2-nitro-4-N-(β-hydroxyethyl)amino-5(dimethyl)amino-ethyl!thioparaphenylenediamine;

2-nitro-5-(β-aminoethyl)thioparaphenylenediamine;

2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-methylthioaniline; and saltsthereof.

The present invention further relates to a process for the preparationof compounds of formula (I).

In this process, a compound of formula (II): ##STR2## in which R₁, R₂,R₃ and R₄ are defined as indicated for the compounds of the formula (I)above, and X is a halogen atom selected from chlorine, bromine andiodine; is reacted with a thiol of the formula (III):

    ASZ                                                        (III)

in which Z is defined as indicated above in the formula (I), and A is ahydrogen, sodium or potassium atom; to give a compound of the formula(I) in which n =0: ##STR3##

The substitution of the halogen group X is effected in a solvent such as1,2-dimethoxyethane, dimethylformamide, N-methylpyrrolidone or dioxane.The reaction temperature may range from room temperature to the refluxtemperature of the reaction medium. The hydrohalic acid "acceptors"which are preferably used are selected from sodium hydroxide, potassiumhydroxide, triethylamine, sodium, potassium and calcium carbonates andthe sodium salts of the thiols used.

In a second step, the compounds of formula (I) in which n is other thanzero then undergo an oxidation appropriate to the value of n which it isdesired to obtain. This oxidation is effected in a solvent medium in thepresence of a conventional oxidizing agent for sulphur, such as apersulphate. Potassium monopersulphate may be mentioned as an example.This oxidation is preferably effected at a temperature ranging fromabout zero to 40° C. The compounds of formula (I) above are preferablyprepared at atmospheric pressure, but they can also be prepared underpressure.

The compounds of formula (I) above can be used as dyestuffs and inparticular as direct dyestuffs for the dyeing of keratin fibres, and inparticular human keratin fibres such as hair. These compounds give thehair a predominantly red colouration.

The invention therefore further relates to a dyeing composition for thedirect dyeing of keratin fibres, in particular human hair, in which atleast one compound of the formula (I) indicated above, or one of thecosmetically acceptable salts thereof, is present in an aqueous,alcoholic or aqueous-alcoholic vehicle.

The compounds of the invention are particularly valuable for obtaining avariety of tints in association with other direct dyestuffs andespecially with the conventional nitrobenzene dyestuffs.

In a preferred embodiment, the dyeing composition according to theinvention contains a compound of the formula (I), or one of itscosmetically acceptable salts, in association with one or more yellow oryellow-green nitrobenzene dyestuffs and gives, on grey hair with a 90%white component, a hue ranging from 2.4 Y to 0.2 YR on the MUNSELLcircle (see the publication Official Digest, April 1975, page 375, FIG.2), the disclosure of which is incorporated herein by reference.

The inventors have found that, when using the dyestuff of the formula(I) in association with one or more conventional yellow or yellow-greendyestuffs, natural hues can be obtained which are more resistant towashing, light, the weather and perspiration than when using thedyestuffs of the prior art, especially on grey natural hair with a 90%white component or on permed grey hair.

In a more particularly preferred embodiment of the present invention,the compound of the formula (I) is associated with yellow oryellow-green dyestuffs selected from the following compounds:

1-(β-hydroxyethoxy-3-methylamino-4-nitrobenzene;

1-(methylamino)-2-nitro-5-(β,γ-dihydroxypropyl)oxybenzene;

1-(β-hydroxyethylamino)-2-methoxy-4-nitrobenzene;

1-(β-aminoethylamino)-2-nitro-5-methoxybenzene;

1,3-di(β-hydroxyethylamino)-4-nitro-6-chlorobenzene;

1-amino-2-nitro-6-methylbenzene;

1-(β-hydroxyethylamino)-2-hydroxy-4-nitrobenzene;

N-(β-hydroxyethyl)-2-nitro-4-trifluoromethylaniline;

4-β-hydroxyethylamino-3-nitrobenzenesulphonic acid;

4-ethylamino-3-nitrobenzoic acid;

4-(β-hydroxyethyl)amino-3-nitrochlorobenzene;

4-(β-hydroxyethyl)amino-3-nitromethylbenzene;

4-(β,γ-dihydroxypropyl)amino-3-nitrotrifluoromethylbenzene;

1β-ureidoethylamino-4-nitrobenzene;

O,N-bis(β-hydroxyethyl)-2-amino-5-nitrophenol;

1,3-diamino-4-nitrobenzene;

1-hydroxy-2-amino-5-nitrobenzene;

1-amino-2- tris(hydroxymethyl)methyl!amino-5-nitrobenzene;

1-(β-hydroxyethyl)amino-2-nitrobenzene; and

4-(β-hydroxyethylamino)-3-nitrobenzamide.

The compounds of the formula (I) according to the invention can also beassociated with blue nitrobenzene dyestuffs such as, for example:

1-(β-hydroxyethyl)amino-4-N,N-bis(β-hydroxyethyl)amino-2-nitrobenzene;

1-(γ-hydroxypropyl)amino-4-N,N-bis(β-hydroxyethyl)-amino-2-nitrobenzene;

1-(β-hydroxyethyl)amino-4-(N-methyl,N-β-hydroxyethyl)-amino-2-nitrobenzene;

1-(β-hydroxyethyl)amino-4-(N-ethyl,N-β-hydroxyethyl)-amino-2-nitrobenzene;

1-(β,γ-dihydroxypropyl)amino-4-(N-ethyl,N-β-hydroxyethyl)-amino-2-nitrobenzene;and

the 2-nitroparaphenylenediamines of formula (IV): ##STR4## in which: R₅is a C₁ -C₄ -alkyl, β-hydroxyethyl, β-hydroxypropyl or γ-dihydroxypropylradical; and

R₆ and R₇, independently of one another, represent a β-hydroxyethyl,β-hydroxypropyl, γ-hydroxypropyl or β,γ-dihydroxypropyl radical; atleast one of the radicals R₅, R₆ or R₇ being a γ-hydroxypropyl radicaland it being impossible for R₅ and R₆ to be a β-hydroxyethyl radicalsimultaneously when R₇ is a γ-hydroxypropyl radical, as described inFrench patent application FR 92-07515, the disclosure of which isincorporated herein by reference.

The concentration of a compound of the formula (I), expressed as thefree base, preferably ranges from 0.01 to 10% by weight, and morepreferably ranges from 0.1 to 5% by weight, based on the total weight ofthe dyeing composition.

The total concentration of yellow and/or yellow-green and/or bluedyestuffs preferably ranges from about 0.05 to 3% by weight, based onthe total weight of the dyeing composition.

Other nitrobenzene dyestuffs can of course be added to the associationsof compounds of the formula (I) and yellow, yellow-green or bluedyestuffs according to the invention, examples being red dyestuffsselected from the following compounds:

1-hydroxy-3-nitro-4-(γ-hydroxypropylamino)benzene;

N-(β-hydroxyethyl)amino-3-nitro-4-aminobenzene;

1-amino-3-methyl-4-(β-hydroxyethyl)amino-6-nitro-benzene;

1-hydroxy-3-nitro-4-N-β-hydroxyethylaminobenzene;

1,4-diamino-2-nitrobenzene;

1-amino-2-nitro-4-methylaminobenzene;

N-(β-hydroxyethyl)-2-nitroparaphenylenediamine;

1-amino-2-nitro-4-(β-hydroxyethylamino)-5-chlorobenzene;

2-nitro-4-aminodiphenylamine; and

1-amino-3-nitro-6-hydroxybenzene.

It is also possible to add orange nitrobenzene dyestuffs selected fromthe following compounds:

1-(β-aminoethyl)amino-2-nitro-4-(β-hydroxyethyl)oxybenzene;

1-(β,γ-dihydroxypropyl)oxy-3-nitro-4-(β-hydroxyethyl)aminobenzene;

1-hydroxy-3-nitro-4-aminobenzene;

1-hydroxy-2-amino-4,6-dinitrobenzene;

1-methoxy-3-nitro-4-(β-hydroxyethylamino)benzene;

2-nitro-4'-hydroxydiphenylamine; and

1-amino-2-nitro-4-hydroxy-5-methylbenzene.

It is further possible to add other direct dyestuffs such as azodyestuffs, anthraquinone dyestuffs, dyestuffs derived fromtriarylmethane or basic dyestuffs, among which the dyestuffs known underthe names Basic Brown 16, Basic Yellow 57, Basic Red 76 and Basic Blue99 in the COLOR INDEX, 3rd edition, may be mentioned more particularly.

The proportion of these additional red or orange nitrobenzene dyestuffsor other direct dyestuffs can range from about 0.05 to 10% by weight,based on the total weight of the dyeing composition.

The compounds of the formula (I) can also be incorporated into dyeingcompositions containing oxidative dyestuffs such as oxidative bases andcouplers, so as to enrich with sheens the hues obtained with theseoxidative dyestuffs.

As an appropriate vehicle, the dyeing compositions according to theinvention can comprise water and/or cosmetically acceptable organicsolvents, and more particularly, comprise alcohols such as ethylalcohol, isopropyl alcohol, benzyl alcohol and phenylethyl alcohol, orglycols or glycol ethers such as, for example, ethylene glycol and itsmonomethyl, monoethyl and monobutyl ethers, propylene glycol, butyleneglycol, dipropylene glycol and the alkyl ethers of diethylene glycol,such as, for example, diethylene glycol monoethyl ether or monobutylether, in concentrations preferably ranging from 0.5 to 20% by weight,and more preferably ranging from 2 to 10% by weight, based on the totalweight of the composition.

Fatty amides, such as the mono- and di-ethanolamides of acids derivedfrom copra, lauric acid or oleic acid, can also be added to thecomposition according to the invention in concentrations whichpreferably range from 0.05 to 10% by weight.

Anionic, cationic, non-ionic, amphoteric or zwitterionic surfactants, ormixtures thereof, can also be added to the composition according to theinvention. The surfactants are preferably present in the compositionaccording to the invention in proportions which range from about 0.1 to50% by weight, and more preferably range from about 1 to 20% by weight,based on the total weight of the composition.

Anionic surfactants, used by themselves or in a mixture, may bepreferably mentioned among the surfactants, examples being the alkalimetal salts, the magnesium salts, the ammonium salts, the amine salts orthe alkanolamine salts of the following compounds:

alkylsulphates, alkyl-ether-sulphates, ethoxylated or non-ethoxylatedalkylamidesulphates;

alkylsulphonates, alkylamidesulphonates, alphaolefinsulfonates;

alkylsulphoacetates, alkylphosphates; and

fatty acids such as lauric, myristic, oleic, ricinoleic, palmitic andstearic acids, acids of copra oil or hydrogenated copra oil, andcarboxylic acids of polyglycol ethers, the alkyl radicals of thesecompounds preferably having a linear chain of 12 to 18 carbon atoms.

Fatty amine salts, quaternary ammonium salts such asalkyldimethylbenzylammonium, alkyltrimethylammonium,alkyldimethylhydroxybenzylammonium and dimethylalkyl-ammonium chloridesand bromides, alkylpyridinium salts and imidazoline derivatives may bepreferably mentioned as cationic surfactants. The alkyl groups of theabove-mentioned quaternary ammonium derivatives are long-chain groupspreferably having from 12 to 18 carbon atoms. Amine oxides may also bementioned among these compounds of cationic character.

Alkylamino monopropionates and dipropionates, betaines such asalkylbetaines, N-alkylsulphobetaines and N-alkylaminobetaines, the alkylradical having from 8 to 22 carbon atoms, and cycloimidinium compoundssuch as alkylimidazolines, may be mentioned in particular among theamphoteric surfactants which can be used.

The following may be mentioned among the non-ionic surfactants which canoptionally be used in the compositions according to the invention:polyglycerolated alcohols, α-diols, alkylphenols and amides, thesecompounds preferably containing a C₈ -C₁₈ fatty chain; polyethoxylatedfatty alcohols, alkylphenols and acids, these compounds preferablycontaining a C₈ to C₁₈ fatty chain; condensation products of ethyleneoxide and propylene oxide with fatty alcohols; polyethoxylated fattyamides preferably containing at least 5 moles of ethylene oxide; andpolyethoxylated fatty amines.

The thickening products which can be added to the composition accordingto the invention can advantageously be selected from the groupcomprising sodium alginate, gum arabic, guar gum, carob gum, xanthangum, cellulose derivatives such as methyl cellulose, hydroxyethylcellulose, hydroxypropyl methyl cellulose and the sodium salt ofcarboxymethyl cellulose, and acrylic acid polymers.

It is also possible to use mineral thickeners such as bentonite. Thesethickeners are used by themselves or in a mixture and are preferablypresent in a proportion which ranges from about 0.2 to 5% by weight,based on the total weight of the composition, and more preferably rangesfrom about 0.5 to 3% by weight.

The dyeing composition according to the invention can be formulated atacidic, neutral or alkaline pH; it being preferable for the pH to rangefrom 4 to 11, and more preferable for the pH to range from 5 to 10.Alkanolamines and alkali metal or ammonium hydroxides and carbonates maybe mentioned among the alkalizing agents which can preferably be used.Lactic acid, acetic acid, tartaric acid, phosphoric acid, hydrochloricacid and citric acid may be mentioned among the acidifying agents whichcan preferably be used.

The dyeing composition according to the invention can also contain avariety of customary adjuvants such as antioxidants, perfumes,sequestering agents, film-forming products and treating agents,dispersants, hair conditioners, preservatives, opacifiers and any otheradjuvant normally used in cosmetics.

The dyeing composition according to the invention can be presented inthe various forms conventionally used for hair dyeing, such as thickenedor gelled liquids, creams, aerosol foams or any other forms appropriatefor the dyeing of keratin fibres.

The present invention further relates to a method of dyeing keratinfibres, and especially human keratin fibres such as hair, whichcomprises allowing the above-defined dyeing composition to act on thedry or wet keratin fibres. The composition according to the inventioncan be used as a no-rinse lotion, i.e. the composition according to theinvention is applied to the keratin fibres, which are then dried withoutintermediate rinsing. In the other modes of application, the dyeingcomposition according to the invention is applied to the keratin fibresfor a period preferably ranging from about 3 to 60 minutes, and morepreferably from 5 to 45 minutes, and the fibres are rinsed, optionallywashed and rinsed again, and then dried.

The following Examples are intended to illustrate the invention withouthowever limiting its scope.

PREPARATORY EXAMPLES Example 1

Preparation of 2-nitro-5-methylthioparaphenylenediamine

46.9 g (0.25 mol) of 2-nitro-5-chloroparaphenylenediamine were added inportions to a suspension of 25 g (0.35 mol) of sodium thiomethylate in350 ml of dimethoxyethane at room temperature.

The reaction was exothermic and the temperature was kept between 25° C.and 30° C. by cooling.

When the addition was complete, the mixture was stirred for half an hourand poured into 2 kg of iced water. The crystalline precipitate wasfiltered off, made into a paste again with water and dried.

This gave dark brown crystals (48.9 g) which melted at 168° C.(recrystallization from 96° ethanol), whose elemental analysiscalculated for C₇ H₉ N₃ O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             42.20     4.55   21.09   16.06                                                                              16.09                                  Found    42.37     4.59   21.08   16.08                                                                              16.19                                  ______________________________________                                    

Example 2

Preparation of 2-nitro-5-ethylthioparaphenylenediamine

This compound was prepared by the procedure described for Example 1.

18.7 g (0.1 mol) of 2-nitro-5-chloro-para-phenylenediamine and 12.6 g(0.15 mol) of sodium thioethylate were used as the starting materials togive brick-red crystals (21.0 g) melting at 142° C. (recrystallizationfrom ethyl acetate), whose elemental analysis calculated for C₈ H₁₁ N₃O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             45.06     5.20   19.70   15.00                                                                              15.04                                  Found    45.17     5.20   19.74   15.14                                                                              15.14                                  ______________________________________                                    

Example 3

Preparation of 2-nitro-5-butylthioparaphenylenediamine

This compound was prepared by the procedure described for Example 1.

28.1 g (0.15 mol) of 2-nitro-5-chloroparaphenylenediamine and 24.7 g(0.22 mol) of sodium thiobutylate were used as the starting materials togive 35.7 g of red crystals melting at 129° C. (recrystallization fromethyl acetate), whose elemental analysis calculated for C₁₀ H₁₅ N₃ O₂ Swas:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             49.77     6.27   17.41   13.26                                                                              13.29                                  Found    49.88     6.32   17.27   13.40                                                                              13.31                                  ______________________________________                                    

Example 4

Preparation of 2-nitro-5-β-hydroxyethylthioparaphenylenediamine

A suspension of 18.7 g (0.1 mol) of2-nitro-5-chloroparaphenylenediamine, 20.7 g (0.15 mol) of potassiumcarbonate and 11.7 g (0.15 mol) of 2-mercaptoethanol in 100 ml ofdimethoxyethane was refluxed for one hour.

The reaction medium was poured into 600 g of iced water. The crystallineprecipitate was filtered off, made into a paste again with water anddried.

This gave 22.5 g of dark garnet-red crystals which melted at 161° C.(recrystalization from 96° ethanol), whose elemental analysis calculatedfor C₈ H₁₁ N₃ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             41.91     4.84   18.33   20.94                                                                              13.99                                  Found    42.04     4.91   18.19   21.22                                                                              13.76                                  ______________________________________                                    

Example 5

Preparation of 2-nitro-5-(β,γ-dihydroxypropyl)thioparaphenylenediamine

This compound was prepared by the procedure described for Example 4.

18.7 g (0.1 mol) of 2-nitro-5-chloro-para-phenylenediamine and 16.2 g(0.15 mol) of 3-mercaptopropane-1, 2-diol were used as the startingmaterials to give dark brown-red crystals (25.4 g) which melted at 164°C. (recrystallization from 96° ethanol), whose elemental analysiscalculated for C₉ H₁₃ N₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             41.69     5.05   16.21   24.68                                                                              12.37                                  Found    41.75     5.10   16.06   24.91                                                                              12.58                                  ______________________________________                                    

Example 6

Preparation of1,4-N-di(β-hydroxyethyl)amino-2-nitro-5-ethoxyethylthiobenzene

This compound was prepared by the procedure described for Example 4.

8.3 g (0.03 mol) of1,4-N-di(β-hydroxyethyl)amino-2-nitro-5-chlorobenzene and 4.8 g (0.045mol ) of 2-ethoxyethanethiol were used as the starting materials to givebrown crystals (9.8 g) which melted at 110° C. (recrystallization fromethanol), whose elemental analysis calculated for C₁₄ H₂₃ N₃ O₅ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             48.68     6.71   12.16   23.16                                                                              9.28                                   Found    48.55     6.67   12.14   23.34                                                                              9.26                                   ______________________________________                                    

Example 7

Preparation of2-nitro-4-N-(β-hydroxyethyl)amino-5-β-hydroxyethylthioaniline

This compound was prepared by the procedure described for Example 4.

23.1 g (0.1 mol) of 2-nitro-4-N-(β-hydroxyethyl)amino-5-chloroanilineand 11.7 g (0.15 mol) of 2-mercaptoethanol were used as the startingmaterials to give 21.7 g of brown-orange crystals melting at 166° C.,whose elemental analysis calculated for C₁₀ H₁₅ N₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             43.95     5.53   15.37   23.42                                                                              11.73                                  Found    44.07     5.61   15.42   23.50                                                                              11.72                                  ______________________________________                                    

Example 8

Preparation of 2-nitro-5-(paramethoxybenzyl)thioparaphenylenediamine

This compound was prepared by the procedure described for Example 4.

37.5 g (0.2 mol) of 2-nitro-5-chloro-para-phenylenediamine and 61.7 g(0.4 mol) of (4-methoxyphenyl)methanethiol were used as the startingmaterials to give, after recrystallization from 96° ethanol, dark browncrystals (34.6 g) melting at 140° C., whose elemental analysiscalculated for C₁₄ H₁₅ N₃ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             55.07     4.95   13.76   15.72                                                                              10.50                                  Found    55.07     4.97   13.75   15.93                                                                              10.34                                  ______________________________________                                    

Example 9

Preparation of 2-nitro-4-N-(β-aminoethyl)amino-5-methylthioaniline

This compound was prepared by the procedure described for Example 1.

46.8 g (0.2 mol) of 2-nitro-4-N-(β-aminoethyl)amino-5-chloroaniline and25 g (0.35 mol) of sodium thiomethylate were used as the startingmaterials to give dark red crystals (43.4 g) melting at 153° C.(recrystallization from isopropyl acetate), whose elemental analysiscalculated for C₉ H₁₄ N₄ O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             44.61     5.82   23.12   13.21                                                                              13.23                                  Found    44.69     5.91   23.06   13.46                                                                              13.39                                  ______________________________________                                    

Example 10

Preparation of 2-nitro-4-N-(diethylaminoethyl)amino-5-methylthioaniline

This compound was prepared by the procedure described for Example 1

5.0 g (0.0174 mol) of2-nitro-4-N-(diethylaminoethyl)amino-5-chloroaniline and 1.9 g (0.026mol) of sodium thiomethylate were used as the starting materials to givebrown-red crystals (4.8 g) melting at 105° C. (recrystallization fromisopropyl acetate), whose elemental analysis calculated for C₁₃ H₂₂ N₄O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             52.33     7.43   18.78   10.72                                                                              10.74                                  Found    52.56     7.46   18.81   10.90                                                                              10.66                                  ______________________________________                                    

Example 11

Preparation of 2-nitro-4-N-(diethylaminoethyl)amino-5-ethylthioaniline

This compound was prepared by the procedure described for Example 1.

5.0 g (0.0174 mol ) of2-nitro-4-N-(diethylaminoethyl)amino-5-chloroaniline and 2.2 g (0.026mol) of sodium thioethylate were used as the starting materials to give5.1 g of brown-red crystals melting at 61° C., whose elemental analysiscalculated for C₁₄ H₂₄ N₄ O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             53.82     7.74   17.93   10.24                                                                              10.26                                  Found    53.79     7.80   17.93   10.35                                                                              10.29                                  ______________________________________                                    

Example 12

Preparation of2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-methylthioaniline

This compound was prepared by the procedure described for Example 1.

18.3 g (0.07 mol) of2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-chloroaniline and 9.8 g (0.14mol ) of sodium thiomethylate were used as the starting materials togive, after purification by passage over a medium pressure column ofsilica gel (ethyl acetate/heptane gradient), brown-red crystals (6.2 g)melting at 133° C., whose elemental analysis calculated for C₁₀ H₁₅ N₃O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             43.95     5.53   15.37   23.42                                                                              11.73                                  Found    43.84     5.51   15.26   23.71                                                                              11.80                                  ______________________________________                                    

Example 13

Preparation of2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-acetylaminoethylthioaniline

A suspension of 55.6 g (0.467 mol) of N-(2-mercaptoethyl) acetamide and15.8 g (0.24 mol) of 85% powdered potassium hydroxide in 300 ml ofdimethoxyethane was heated at 45° C. until the potassium hydroxide haddissolved.

49.0 g (0.187 mol ) of2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-chloroaniline were added inportions, the temperature being kept at 45° C.

When the addition was complete, the mixture was stirred for one hour andpoured into 1 liter of iced water. The crystalline precipitate wasfiltered off, made into a paste again with water and recrystallized from96° ethanol under reflux.

This gave claret-coloured crystals (32.9 g) melting at 178° C., whoseelemental analysis calculated for C₁₃ H₂₀ N₄ O₅ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             45.34     5.85   16.27   23.23                                                                              9.31                                   Found    45.38     5.91   16.24   22.99                                                                              9.27                                   ______________________________________                                    

Example 14

Preparation of 2-nitro-5-acetylaminoethylthioparaphenylenediamine

This compound was prepared by the procedure described for Example 13.

46.9 g (0.25 mol) of 2-nitro-5-chloro-paraphenylenediamine and 74.5 g(0.625 mol) of N-(2-mercaptoethyl)acetamide were used as the startingmaterials to give 64.3 g of red crystals (recrystallization from 96°ethanol) melting at 162° C., whose elemental analysis calculated for C₁₀H₁₄ N₄ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             44.43     5.22   20.73   17.76                                                                              11.86                                  Found    44.56     5.24   20.64   17.72                                                                              11.81                                  ______________________________________                                    

Example 15

Preparation of 2-nitro-5-(β-aminoethyl)thioparaphenylenediaminedihydrochloride

A solution of 20.3 g (0.075 mol) of2-nitro-5-acetylaminoethylthioparaphenylenediamine, obtained in Example14, in 65 ml of a 36% aqueous solution of hydrochloric acid was refluxedfor 3 hours.

The reaction medium (yellow suspension) was cooled in an ice bath andfiltered. It was made into a paste again with absolute ethanol and driedto give 8.3 g of yellow crystals melting with decomposition at 240°-243°C., whose elemental analysis calculated for C₈ H₁₂ N₄ O₂ S.2HCl.1/2C₂ H₅OH was:

    ______________________________________                                        %        C      H        N    O      S    Cl                                  ______________________________________                                        Calculated                                                                             33.34  5.28     17.28                                                                              12.34  9.89 21.87                               Found    33.27  4.95     17.03                                                                              12.74  10.17                                                                              21.49                               ______________________________________                                    

Example 16

Preparation of 2-nitro-5- (dimethyl)aminoethyl!thioparaphenylenediaminemonohydrate

The procedure described for Example 4 was used with two modifications:the solvent used was N-methyl-pyrrolidone and the reaction temperaturewas that of the boiling water bath (95°-100°C.).

37.5 g (0.2 mol) of 2-nitro-5-chloro-para-phenylenediamine and 42.5 g(0.3 mol) of 2-dimethylaminoethanethiol hydrochloride were used as thestarting materials to give (after recrystallization from 96° ethanol)48.1 g of red-orange crystals melting at 122° C., whose elementalanalysis calculated for C₁₀ H₁₆ N₄ O₂ S.H₂ O was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             43.78     6.61   20.42   17.50                                                                              11.69                                  Found    44.04     6.59   20.45   17.00                                                                              11.97                                  ______________________________________                                    

Example 17

Preparation of 2-nitro-4-N-(β-hydroxyethyl)amino-5-(dimethyl)aminoethyl!thioparaphenylenediamine

This compound was prepared by the procedure described for Example 16.

23.1 g (0.1 mol) of2-nitro-4-N-(β-hydroxyethyl)amino-5-chloro-paraphenylenediamine and 21.2g (0.15 mol) of 2-dimethylaminoethanethiol hydrochloride were used asthe starting materials to give, after recrystallization from 96°ethanol, brown-red crystals (17.6 g) melting at 133° C., whose elementalanalysis calculated for C₁₂ H₂₀ N₄ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             47.98     6.71   18.65   15.98                                                                              10.67                                  Found    48.01     6.77   18.74   15.94                                                                              10.57                                  ______________________________________                                    

Example 18

Preparation of 2-nitro-5-(β-aminoethyl)thioparaphenylenediamine

This compound was prepared by the procedure described for Example 16.

18.7 g (0.1 mol) of 2-nitro-5-chloropara-phenylenediamine and 17.0 g(0.15 mol) of 2-aminoethanethiol hydrochloride were used as the startingmaterials to give brown-red crystals (18.0 g) melting at 149° C.(recrystallization from 96° ethanol), whose elemental analysiscalculated for C₈ H₁₂ N₄ O₂ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             42.09     5.30   24.54   14.02                                                                              14.05                                  Found    42.20     5.35   24.31   14.15                                                                              14.17                                  ______________________________________                                    

Example 19

Preparation of 2-nitro-4-amino-5-(β-hydroxypropyl)thio-N-(methyl)aniline

The procedure described for the preparation of Example 4 was used.

11.5 g (0.057 mol) of 2-nitro-4-amino-5-chloro-N-(methyl)aniline and 7.8g (0.085 mol) of 1-mercaptopropan-2-ol were used as the startingmaterials to give dark brown crystals (14.3 g) melting at 152° C.(recrystallization from 96° ethanol), whose elemental analysiscalculated for C₁₀ H₁₅ N₃ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             46.68     5.88   16.33   18.65                                                                              12.46                                  Found    46.61     5.91   16.38   18.81                                                                              12.26                                  ______________________________________                                    

Example 20

Preparation of2-nitro-4-amino-5-(parahydroxyphenyl)thio-N-(methyl)aniline

This compound was prepared by the procedure described for Example 4.

11.5 g (0.057 mol) of 2-nitro-4-amino-5-chloro-N-(methyl)aniline and11.9 g (0.085 mol) of 4-mercaptophenol were used as the startingmaterials to give brown-orange crystals (11.3 g) recrystallized from 96°ethanol and melting at 206° C., whose elemental analysis calculated forC₁₃ H₁₃ N₃ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             53.60     4.50   14.42   16.48                                                                              11.01                                  Found    53.41     4.58   14.21   16.95                                                                              10.90                                  ______________________________________                                    

Example 21

Preparation of 2-nitro-5-ethoxycarbonylethylthioparaphenylenediamine

This compound was prepared by the procedure described for Example 16.

22.5 g (0.12 mol) of 2-nitro-5-chloropara-phenylenediamine and 25.0 g(0.186 mol) of ethylcarbonylethylthiol were used as the startingmaterials to give bronze-coloured crystals (21.6 g) melting at 120° C.,whose elemental analysis calculated for C₁₁ H₁₅ N₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             46.31     5.30   14.73   22.43                                                                              11.24                                  Found    46.31     5.41   14.66   22.23                                                                              11.41                                  ______________________________________                                    

Example 22

Preparation of 2-nitro-5-methylsulphinylparaphenylenediamine

A solution of 35.3 g (0.115 mol) of potassium monopersulphate (triplesalt) in 300 ml of water was rapidly added dropwise to a suspension,cooled to 0° C., of 19.9 g (0.1 mol) of2-nitro-5-methylthiopara-phenylenediamine (obtained in Example 1) in 300ml of acetone, the temperature being kept at +10° C.

The mixture was stirred for one hour at +10° C., 300 g of ice were addedand the reaction medium was neutralized with a dilute solution of sodiumhydroxide. It was extracted with ethyl acetate and the extract was driedover sodium sulphate and evaporated to dryness under reduced pressure.

Purification by passage over a column of silica gel (heptane/ethylacetate gradient) gave dark red crystals (7.9 g) melting at 204° C.,whose elemental analysis calculated for C₇ H₉ H₃ O₃ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             39.06     4.21   19.52   22.30                                                                              14.90                                  Found    39.20     4.28   19.58   22.31                                                                              14.83                                  ______________________________________                                    

Example 23

Preparation of 2-nitro-5-mesylparaphenylenediamine

1st step: Synthesis of 1,4-di-N-acetylamino-2-nitro-5-methylthiobenzene

A mixture of 59.7 g (0.3 mol) of2-nitro-5-methylthioparaphenylenediamine (obtained in Example 1) and 66ml of acetic anhydride in 350 ml of dioxane was heated for one hour in aboiling water bath.

The yellow suspension was cooled in an ice bath.

The crystalline precipitate was filtered off, washed with dioxane andthen with petroleum ether and dried.

This gave yellow crystals (71.7 g) melting at 247° C., whose elementalanalysis calculated for C₁₁ H₁₃ N₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             46.64     4.63   14.83   22.59                                                                              11.32                                  Found    46.68     4.64   14.89   22.60                                                                              11.14                                  ______________________________________                                    

2nd step:

A solution of 103 g (0.335 mol) of potassium monopersulphate (triplesalt) in 700 ml of water was added rapidly at room temperature to asuspension of 38.0 g (0.134 mol) of the compound obtained above in step1 in 700 ml of acetone, the temperature being allowed to rise to 30° C.

The mixture was stirred for 2 hours at room temperature and diluted with700 g of iced water.

The crystalline precipitate was filtered off, made into a paste againwith water and dried.

This gives yellow crystals (36.4 g) melting at 256° C.(recrystallization from acetic acid), whose elemental analysiscalculated for C₁₁ H₁₃ N₃ O₆ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             41.90     4.16   13.33   30.45                                                                              10.17                                  Found    42.06     4.25   13.17   30.54                                                                              10.22                                  ______________________________________                                    

3rd step

The compound obtained above (step 2--36.4 g) was deacetylated by heatingin a boiling water bath for 30 min in a mixture of 200 ml of 36% aqueoushydrochloric acid and 40 ml of acetic acid.

The resulting mixture was cooled in an ice bath.

The crystalline hydrochloride was filtered off and taken up with 200 mlof aqueous ammonia.

The crystalline precipitate was filtered off, made into a paste againwith water and dried.

This gave brown-violet crystals (12.8 g) of the expected product meltingat 221° C., whose elemental analysis calculated for C₇ H₉ N₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             36.36     3.92   18.17   27.68                                                                              13.87                                  Found    36.87     4.01   18.05   27.52                                                                              13.89                                  ______________________________________                                    

Example 24

Preparation of 2-nitro-5-trimethylammonioethylthioparaphenylenediaminemethylsulphate

4.8 ml (0.05 mol) of dimethyl sulphate were added to a suspension, atroom temperature, of 13.7 g (0.05 mol) of2-nitro-5-(dimethylaminoethylthio)paraphenylenediamine monohydrate,prepared in Example 16, in 250 ml of ethyl acetate.

The mixture was stirred for 4 hours at room temperature and thecrystalline precipitate was filtered off and washed with ethyl acetate.

After drying, dark brown-red crystals (18.8 g) melting at 153°-154° C.were obtained, whose elemental analysis calculated for C₁₁ H₁₉ N₄ O₂S.CH₃ O₄ S was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             37.69     5.80   14.65   25.10                                                                              16.77                                  Found    37.72     5.71   14.52   24.89                                                                              16.98                                  ______________________________________                                    

Example 25

Preparation of1-N-(β-hydroxyethyl)amino-2-nitro-4-N,N-bis(β-hydroxyethyl)amino-5-isopropyl-thiobenzenemonohydrochloride

1st step: Synthesis of1-N-(β-hydroxyethyl)amino-2-nitro-4-N,N-(di-β-hydroxyethyl)amino-5-chlorobenzene

A suspension of 18.7 g (0.1 mol) of2-nitro-5-chloroparaphenylenediamine, 30 g of calcium carbonate and 62.5g (0.5 mol) of 2-bromoethanol in 50 ml of water was heated for 12 hoursin a boiling water bath.

Three volumes of iced water were added to the reaction medium,extraction was carried out with ethyl acetate and the extract was driedover sodium sulphate, filtered and evaporated to dryness under reducedpressure.

The orange oil obtained was purified by passage over a column of silicagel (heptane/ethyl acetate gradient).

This gave yellow-orange crystals melting at 94° C., whose elementalanalysis calculated for C₁₂ H₁₈ ClN₃ O₅ was:

    ______________________________________                                        %        C         H      Cl      N    O                                      ______________________________________                                        Calculated                                                                             45.08     5.67   11.09   13.14                                                                              25.02                                  Found    45.11     5.71   10.83   13.05                                                                              25.02                                  ______________________________________                                    

2nd step

The compound obtained above in the 1st step (9.6 g-0.03 mol) and 5.9 g(0.06 mol) of sodium thioisopropylate were reacted by the proceduredescribed for Example 1.

After purification and conversion to the hydrochloride in absoluteethanol, this gave yellow crystals melting at 162°-164° C., whoseelemental analysis calculated for C₁₅ H₂₅ N₃ O₅ S.HCl was:

    ______________________________________                                        %        C      H        N    O      S    Cl                                  ______________________________________                                        Calculated                                                                             45.51  6.62     10.61                                                                              20.21  8.10 8.95                                Found    45.32  6.52     10.61                                                                              20.01  8.34 8.66                                ______________________________________                                    

Example 26

Preparation of 2-nitro-5-sulphoethylthioparaphenylenediamine monohydrate

The procedure described for Example 16 was used, the potassium carbonatebeing replaced with sodium carbonate.

18.7 g (0.1 mol) of 2-nitro-5-chloropara-phenylenediamine and 24.6 g(0.15 mol) of the sodium salt of 2-mercaptoethanesulphonic acid wereused as the starting materials to give yellow-orange crystals (27.6 g)melting above 260° C., whose elemental analysis calculated for C₈ H₁₁ N₃O₅ S₂. H₂ O was:

    ______________________________________                                        %        C         H      N       O    S                                      ______________________________________                                        Calculated                                                                             30.86     4.21   13.50   30.83                                                                              20.60                                  Found    30.97     4.18   13.42   30.14                                                                              20.60                                  ______________________________________                                    

EXAMPLES OF DYEING COMPOSITIONS Example 27

The following dyeing composition was prepared:

    ______________________________________                                        2-nitro-5-trimethylammonioethylthioparaphenylene-                                                        0.25   g                                           diamine methylsulphate                                                        N-(β-hydroxyethyl)amino-3-nitro-4-aminobenzene                                                      0.1    g                                           1,4-di-N-(β,γ-dihydroxypropyl)aminoanthraquinone                                              0.05   g                                           N-(β-hydroxyethyl)amino-2-nitroparaphenylenediamine                                                 0.02   g                                           propylene glycol monomethyl ether                                                                        10     g                                           nonylphenol ethoxylated with 9 moles of ethylene                                                         8      g                                           oxide, sold under the name RHODIASURF NP 9 OR by                              RHONE POULENC                                                                 copra diethanolamine sold under the name                                                                 2      g                                           COMPERLAN KD by HENKEL                                                        citric acid                q.s.   pH 9                                        demineralized water        q.s.p. 100 g                                       ______________________________________                                    

The above composition was applied to locks of natural grey hair with a90% white component. It was left on the hair for 30 minutes at roomtemperature. After rinsing and drying, the hair was dyed an iridescentdeep blond color.

Example 28

The following dyeing composition was prepared:

    ______________________________________                                        2-nitro-4-N-(β-hydroxyethyl)amino-5- (dimethyl)-                                                     0.3    g                                          aminoethyl!thioparaphenylenediamine                                           1-β-hydroxyethoxy-3-methylamino-4-nitro-benzene                                                      0.05   g                                          1-hydroxy-3-nitro-4-aminobenzene                                                                          0.03   g                                          1-(β-aminoethylamino)-2-nitro-5-methoxy-benzene                                                      0.1    g                                          propylene glycol monomethyl ether                                                                         10     g                                          nonylphenol ethoxylated with 9 moles of ethylene                                                          8      g                                          oxide, sold under the name RHODIASURF NP 9 OR by                              RHONE POULENC                                                                 copra diethanolamine sold under the name                                                                  2      g                                          COMPERLAN KD by HENKEL                                                        2-amino-2-methylpropan-1-ol                                                                              q.s.   pH 9                                        demineralized water        q.s.p. 100 g                                       ______________________________________                                    

The above composition was applied to locks of natural grey hair with a90% white component. It was left on the hair for 30 minutes at roomtemperature. After rinsing and drying, the hair was dyed a goldencoppery light blond color.

Example 29

The following dyeing composition was prepared:

    ______________________________________                                        2-nitro-5-(β-aminoethyl)thioparaphenylenediamine                                                     0.22   g                                          dihydrochloride                                                               1-hydroxy-3-nitro-4-(γ-hydroxypropylamino)benzene                                                   0.02   g                                          4-(β-hydroxyethyl)amino-3-nitromethyl-benzene                                                        0.03   g                                          1-N,N-(bis-β-hydroxyethyl)amino-3-methyl-4-N-                                                        0.05   g                                          (4'-aminophenylazo)aminobenzene                                               propylene glycol monomethyl ether                                                                         10     g                                          nonylphenol ethoxylated with 9 moles of ethylene                                                          8      g                                          oxide, sold under the name RHODIASURF NP 9 OR by                              RHONE POULENC                                                                 copra diethanolamine sold under the name                                                                  2      g                                          COMPERLAN KD by HENKEL                                                        2-amino-2-methylpropan-1-ol                                                                              q.s.   pH 9                                        demineralized water        q.s.p. 100 g                                       ______________________________________                                    

The above composition was applied to locks of natural grey hair with a90% white component. It was left on the hair for 30 minutes at roomtemperature. After rinsing and drying, the hair was dyed an iridescentcoppery blond color.

Example 30

The following dyeing composition was prepared:

    ______________________________________                                        2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-                                                    0.15   g                                            methylthioaniline                                                             1-N-(β-hydroxyethyl)amino-4-(N-ethyl, N-                                                           0.1    g                                            β-hydroxyethyl)amino-2-nitrobenzene                                      1-(β-aminoethyl)amino-2-nitro-4-(β-                                                           0.07   g                                            hydroxyethyl)oxybenzene                                                       propylene glycol monomethyl ether                                                                       10     g                                            nonylphenol ethoxylated with 9 moles of                                                                 8      g                                            ethylene oxide, sold under the name                                           RHODIASURF NP 9 OR by RHONE POULENC                                           copra diethanolamine sold under the name                                                                2      g                                            COMPERLAN KD by HENKEL                                                        citric acid              q.s.   pH 9                                          demineralized water      q.s.p. 100 g                                         ______________________________________                                    

The above composition was applied to locks of natural grey hair with a90% white component. It was left on the hair for 30 minutes at roomtemperature. After rinsing and drying, the hair was dyed an iridescentcoppery light blond color.

What is claimed is:
 1. A dyeing composition for the direct dyeing ofkeratin fibres which comprises in an aqueous, alcoholic oraqueous-alcoholic vehicle, at least one compound of the formula (I):##STR5## in which: n=0, 1 or 2;R₁, R₂, R₃ and R₄, which may be identicalor different, are a hydrogen atom or a linear or branched C₁ -C₄ -alkyl,a linear or branched C₁ -C₄ -monohydroxyalkyl, a linear or branched C₂-C₄ -polyhydroxyalkyl, a linear or branched C₁ -C₄ -aminoalkyl, a linearor branched C₁ -C₄ -monoalkyl-amino-(C₁ -C₄)-alkyl radical, or a linearor branched C₁ -C₄ -dialkyl-amino-(C₁ -C₄)-alkyl radical; and Z is alinear or branched C₁ -C₄ -alkyl, a linear or branched C₁ -C₄-monohydroxyalkyl, a linear or branched C₂ -C₄ -polyhydroxyalkyl, alinear or branched C₁ -C₄ -aminoalkyl, a linear or branched C₁ -C₄-alkoxy-(C₁ -C₄)-alkyl, a linear or branched C₁ -C₄ -acetylaminoalkyl, alinear or branched C₁ -C₄ -monoalkylamino-(C₁ -C₄)-alkyl or a linear orbranched C₁ -C₄ -dialkylamino-(C₁ -C₄)-alkyl radical, a linear orbranched tri-(C₁ -C₄ -alkylammonio-(C₁ -C₄)-alkyl-(C₁ -C₄)-alkyl halideor tri-(C₁ -C₄)-alkylammonio-(C₁ -C₄)-alkyl-(C₁ -C₄)-alkysulphate, asubstituted or unsubstituted benzyl, a substituted or unsubstitutedphenyl, a linear or branched C₁ -C₄ -sulphoalkyl or a linear or branchedC₁ -C₄ -alkoxycarbonyl-(C₁ -C₄)-alkyl radical; or a cosmeticallyacceptable salt thereof, wherein said at least one compound of theformula (I) or salt thereof is present in an amount effective todirectly dye said keratin fibres.
 2. A dyeing composition according toclaim 1, wherein said keratin fibres are human keratin fibres.
 3. Adyeing composition according to claim 1, wherein the alkyl, hydroxyalkylor alkoxyalkyl radicals of the compound of the formula (I) are selectedfrom methyl, ethyl, propyl, butyl, hydroxyethyl, hydroxypropyl,dihydroxypropyl and ethoxyethyl.
 4. A dyeing composition according toclaim 1, wherein R₁ of the compound of formula (I) is a hydrogen atom.5. A dyeing composition according to claim 3, wherein R₁ of the compoundof formula (I) is a hydrogen atom.
 6. A dyeing composition according toclaim 1 which comprises a compound of formula (I) selectedfrom:2-nitro-5-trimethylammonioethylthioparaphenylenediamine;2-nitro-4-N-(β-hydroxyethyl)amino-5(dimethyl)aminoethyl!thioparaphenylenediamine;2-nitro-5-(β-aminoethyl)thioparaphenylenediamine;2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-methylthioaniline;2-nitro-5-methylthioparaphenylenediamine;2-nitro-5-ethylthioparaphenylenediamine;2-nitro-5-butylthioparaphenylenediamine;2-nitro-5-β-hydroxyethylthioparaphenylenediamine;2-nitro-5-(β,γ-dihydroxypropyl)thioparaphenylenediamine;1,4-N-di(β-hydroxyethyl)amino-2-nitro-5-ethoxyethylthiobenzene;2-nitro-4-N-(β-hydroxyethyl)amino-5-β-hydroxyethylthioaniline;2-nitro-5-(paramethoxybenzyl)thioparaphenylenediamine;2-nitro-4-N-(β-aminoethyl)amino-5-methylthioaniline;2-nitro-4-N-(diethylaminoethyl)amino-5-methylthioaniline;2-nitro-4-N-(diethylaminoethyl)amino-5-ethylthioaniline;2-nitro-4-N-(β,γ-dihydroxypropyl)amino-5-acetylaminoethylthioaniline;2-nitro-5-acetylaminoethylthioparaphenylenediamine; 2-nitro-5-(dimethyl)aminoethyl!thioparaphenylenediamine;2-nitro-5-(β-aminoethyl)thioparaphenylenediamine;2-nitro-4-amino-5-(β-hydroxypropyl)thio-N-(methyl)aniline;2-nitro-4-amino-5-(parahyanoxyphenyl)thio-N-(methyl)aniline;2-nitro-5-ethoxycarbonylethylthioparaphenylenediamine;2-nitro-5-methylsulphinylparaphenylenediamine;2-nitro-5-mesylparaphenylenediamine;1-N-(β-hydroxyethyl)amino-2-nitro-4-N,N-bis(β-hydroxyethyl)amino-5-isopropylthiobenzene;2-nitro-5-sulphoethylthioparaphenylenediamine;or a cosmeticallyacceptable salt thereof.
 7. A dyeing composition according to claim 1,which further comprises at least one yellow or yellow-green nitrobenzenedyestuff with a MUNSELL hue ranging from 2.4 Y to 0.2 YR on grey hairwith a 90% white component.
 8. A dyeing composition according to claim7, wherein said yellow or yellow-green nitrobenzene dyestuff is selectedfrom the followingcompounds:1-β-hydroxyethoxy-3-methylamino-4-nitrobenzene;1-(methylamino)-2-nitro-5-(β,γ-dihydroxypropyl)oxybenzene;1-(β-hydroxyethylamino)-2-methoxy-4-nitrobenzene;1-(β-aminoethylamino)-2-nitro-5-methoxybenzene;1,3-di(β-hydroxyethylamino)-4-nitro-6-chlorobenzene;1-amino-2-nitro-6-methylbenzene;1-(β-hydroxyethylamino)-2-hydroxy-4-nitrobenzene;N-(β-hydroxyethyl)-2-nitro-4-trifluoromethylaniline;4-β-hydroxyethylamino-3-nitrobenzenesulphonic acid;4-ethylamino-3-nitrobenzoic acid;4-(β-hydroxyethyl)amino-3-nitrochlorobenzene;4-(β-hydroxyethyl)amino-3-nitromethylbenzene;4-(β,γ-dihydroxypropyl)amino-3-nitrotrifluoromethylbenzene;1-β-ureidoethylamino-4-nitrobenzene;O,N-bis(β-hydroxyethyl)-2-amino-5-nitrophenol;1,3-diamino-4-nitrobenzene; 1-hydroxy-2-amino-5-nitrobenzene; 1-amino-2-tris(hydroxymethyl)methyl!amino-5-nitrobenzene;1-(β-hydroxyethyl)amino-2-nitrobenzene; and4-(β-hydroxyethylamino)-3-nitrobenzamide.
 9. A dyeing compositionaccording to claim 1, which further comprises at least one bluenitrobenzene dyestuff selected from the followingcompounds:1-(β-hydroxyethyl)amino-4-N,N-bis(β-hydroxyethyl)amino-2-nitrobenzene;1-(γ-hydroxypropyl)amino-4-N,N-bis(β-hydroxyethyl)amino-2-nitrobenzene;1-(β-hydroxyethyl)amino-4-(N-methyl,N-β-hydroxyethyl)amino-2-nitrobenzene;1-(β-hydroxyethyl)amino-4-(N-ethyl,N-β-hydroxyethyl)amino-2-nitrobenzene;1-(β,γ-dihydroxypropyl)amino-4-(N-ethyl,N-β-hydroxyethyl)amino-2-nitrobenzene;andthe 2-nitroparaphenylenediamines of formula (IV) ##STR6## in which:R₅ is a C₁ -C₄ -alkyl, β-hydroxyethyl, β-hydroxypropyl orγ-hydroxypropyl radical; and -R₆ and R₇ independently of one anotherrepresent a β-hydroxyethyl, β-hydroxypropyl, γ-hydroxypropyl orβ,γ-dihydroxypropyl radical; at least one of said radicals R₅, R₆ or R₇being a γ-hydroxypropyl radical; and it being impossible for R₅ and R₆to be a β-hydroxyethyl radical simultaneously when R₇ is aγ-hydroxypropyl radical.
 10. A dyeing composition according to claim 1,which further comprises at least one red nitrobenzene dyestuff selectedfrom the followingcompounds:1-hydroxy-3-nitro-4-(γ-hydroxypropylamino)benzene;N-(β-hydroxyethyl)amino-3-nitro-4-aminobenzene;1-amino-3-methyl-4-(β-hydroxyethyl)amino-6-nitrobenzene;1-hydroxy-3-nitro-4-N-β-hydroxyethylamino-benzene; 1.4-diamino-2-nitrobenzene;1-amino-2-nitro-4-methylaminobenzene;N-(β-hydroxyethyl)-2-nitroparaphenylenediamine;1-amino-2-nitro-4-(β-hydroxyethylamino)-5-chlorobenzene:nitro-4-aminodiphenylamine; and 1-amino-3-nitro-6-hydroxybenzene.
 11. Adyeing composition according to claim 1, which further comprises atleast one orange nitrobenzene dyestuff selected from the followingcompounds:1-(β-aminoethyl)amino-2-nitro-4-(β-hydroxyethyl)oxybenzene;1-(β,γ-dihydroxypropyl)oxy-3-nitro-4-(β-hydroxyethyl)aminobenzene;1-hydroxy-3-nitro-4-aminobenzene; 1-hydroxy-2-amino-4,6-dinitrobenzene;1-methoxy-3-nitro-4-(β-hydroxyethylamino)-benzene;2-nitro-4'-hydroxydiphenylamine; and1-amino-2-nitro-4-hydroxy-5-methylbenzene.
 12. A dyeing compositionaccording to claim 1, which further comprises additional directdyestuffs selected from azo dyestuffs, anthraquinone dyestuffs,triarylmethane derivatives and basic dyestuffs.
 13. A dyeing compositionaccording to claim 1, which contains a compound of formula (I) in aproportion, expressed as a free base, which ranges from 0.01 to 10% byweight, based on the total weight of the composition.
 14. A dyeingcomposition according to claim 13, which contains a compound of formula(I) in proportions, expressed as a free base, which range from 0.1 to 5%by weight, based on the total weight of the composition.
 15. A dyeingcomposition according to claim 1, which further comprises from 0.05 to3% by weight of at least one dyestuff, said dyestuff being a yellow,yellow-green or blue nitrobenzene dyestuff, based on the total weight ofthe composition.
 16. A dyeing composition according to claim 1, whichfurther comprises from 0.05 to 10% by weight of direct dyestuffs otherthan the compounds of formula (I), based on the total weight of thecomposition.
 17. A dyeing composition according to claim 1, whichfurther comprises at least one organic solvent selected from alcohols,glycols and glycol ethers.
 18. A dyeing composition according to claim17, wherein said at least one organic solvent is present in a proportionwhich ranges from 0.5% to 20%, based on the total weight of thecomposition.
 19. A dyeing composition according to claim 18, whereinsaid at least one organic solvent is present in a proportion whichranges from 2% to 10%, based on the total weight of the composition. 20.A dyeing composition according to claim 1, which further comprises atleast one adjuvant selected from fatty amides, anionic, cationic,non-ionic, amphoteric and zwitterionic surfactants and mixtures thereof,thickeners, antioxidants, perfumes, sequestering agents, film-formingagents, hair treating agents, dispersants, hair conditioners,preservatives and opacifiers.
 21. A dyeing composition according toclaim 1, which has a pH ranging from 4 to
 11. 22. A dyeing compositionaccording to claim 21, which has a pH ranging from 5 to
 10. 23. A methodfor the dyeing of keratin fibres, by direct dyeing, which comprisesapplying the dyeing composition according to claim 1 to dry or wetkeratin fibres and drying said keratin fibres without intermediaterinsing.
 24. A method according to claim 23, wherein said keratin fibresare human keratin fibres.
 25. A method according to claim 24, whereinsaid human keratin fibres are hair.
 26. A method for the dyeing ofkeratin fibres, by direct dyeing, which comprises applying the dyeingcomposition according to claim 1 to dry or wet keratin fibres, allowingsaid dyeing composition to act on said keratin fibres for a periodranging from 3 to 60 minutes, rinsing said keratin fibres, and dryingsaid keratin fibres.
 27. A method according to claim 26, wherein saidcomposition is allowed to act on said keratin fibres for a periodranging from 5 to 45 minutes.
 28. A method according to claim 26,wherein following said rinsing of the keratin fibres, said keratinfibres are washed and rinsed again before said drying of said keratinfibres.
 29. A method according to claim 26, wherein said keratin fibresare human keratin fibres.
 30. A method according to claim 29, whereinsaid human keratin fibres are hair.
 31. A dyeing composition accordingto claim 1, wherein said composition is in the form of a thickened orgelled liquid, a cream, or an aerosol foam.
 32. A dyeing compositioncomprising at lease one oxidative dyestuff and a compound of formula(I): ##STR7## in which: n=0, 1 or 2;R₁, R₂, R₃ and R₄, which may beidentical or different, are a hydrogen atom or a linear or branched C₁-C₄ -alkyl, a linear or branched C₁ -C₄ -monohydroxyalkyl, a linear orbranched C₂ -C₄ -polyhydroxyalkyl, a linear or branched C₁ -C₄-aminoalkyl, a linear or branched C₁ -C₄ -monoalkyl-amino-(C₁ -C₄)-alkylradical, or a linear or branched C₁ -C₄ -dialkyl-amino-(C₁ -C₄)-alkylradical; and Z is a linear or branched C₁ -C₄ -alkyl, a linear orbranched C₁ -C₄ -monohydroxyalkyl, a linear or branched C₂ -C₄-polyhydroxyalkyl, a linear or branched C₁ -C₄ -aminoalkyl, a linear orbranched C₁ -C₄ -alkoxy-(C₁ -C₄)-alkyl, a linear or branched C₁ -C₄-acetylaminoalkyl, a linear or branched C₁ -C₄ -monoalkylamino-(C₁-C₄)-alkyl or a linear or branched C₁ -C₄ -dialkylamino-(C₁ -C₄)-alkylradical, a linear or branched tri-(C₁ -C₄)-alkylammmonio-(C₁-C₄)-alkyl-(C₁ -C₄)-alkylhalide or tri-(C₁ -C₄)-alkylammonio-(C₁-C₄)-alkyl-(C₁ C₄)alkylsulphate, a substituted or unsubstituted benzyl,a substituted or unsubstituted phenyl, a linear or branched C₁ -C₄-sulphoalkyl or a linear or branched C₁ -C₄ -alkoxycarbonyl-(C₁-C₄)-alkyl radical; or a cosmetically acceptable salt thereof, whereinsaid at least one oxidative dyestuff and said compound of formula (I) orsalt thereof are present in amounts effective to dye keratin fibres.